Debt from China's interest-free loans, due by the end of 2018, would be written off for some poor African states, Mr Xi said.
Focac will bring together 52 African countries, the African Union (AU) Commission and the People's Republic of China, as equal partners in fostering greater unity and cooperation.
China would be happy to help Africa upgrade its customs and commodities inspection facilities and provide supplies and equipment to improve trade connectivity with the continent, the Chinese leader added. "This year, 69 Kenyan students have received Chinese government scholarships whereas 100 students received scholarships from various Chinese companies", the ambassador said.
The world's second-biggest economy will be hosting the China-Africa summit starting on Monday and South Africa will co-chair that meeting.
But critics warn that the Chinese leader's pet project is burying some countries under massive debt.
"It's hard to think of any country in Africa that has not been touched by China", he said, adding that China rejects the claim of "debt-trap diplomacy".
The ruling Pakistan Tehreek-i-Insaf, whose chief Imran Khan was installed prime minister in August after an election victory, has vowed more transparency amid fears about Islamabad's ability to repay Chinese loans related to the multi-billion-dollar China-Pakistan Economic Corridor.
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Whilst the Gunners will need to do a fair bit of travelling, they'll be happy with the opposition they've been drawn against. Scottish giants Celtic and Rangers both face hard draws as they aim to negotiate the group stages.
Every African country is represented at the business forum apart from eSwatini, self-ruled Taiwan's last African ally that has so far rejected China's overtures to ditch Taipei and recognise Beijing.
Over the past 18 years, FOCAC has become a significant platform for collective dialogue between China and African countries and a leading mechanism for global ties with Africa and also South-South cooperation.
He said: "During the High-Level Dialogue between Chinese and African Leaders, and Business representatives on the margins of FOCAC, the Nigerian delegation is also expected to sign no fewer than 25 MoUs".
The summit is also expected to strengthen the cooperation between China and Africa to a high level with the adoption of the Beijing Declaration and the Beijing Action Plan. He tried to mollify concern Beijing wants to build strategic influence, promising Chinese investment comes with "no political strings attached". More than 180 major Chinese enterprises and thousands of small and medium enterprises have been established in the country.
Chris Kiptoo, Principal Secretary for International Trade, said China already accounts for 25 per cent of Kenya's import bill under the current common external tariff structure of zero per cent, 10 per cent and 25 per cent for raw materials, intermediate goods and final goods respectively.
Aisha, wife of President Muhammadu Buhari, and Halima, one of his daughters, accompanied him on his trip to China.